“”Every school should have a “fix-it lab” where students learn to repair their clothes, bikes and electronics. We should grow up knowing that not everything is disposable, that care and repair are part of living well on this planet.”” https://www.facebook.com/reel/1280502713546957/?mibextid=9drbnH&s=yWDuG2&fs=e
Archive for the ‘Do It Yourself’ Category:
2025-08-12 DIY Rocket Engine!
OMG! https://www.facebook.com/TheBackyardScientistOfficial/videos/970125545097522/?mibextid=9drbnH&s=yWDuG2&fs=e Here’s how to make rocket fuel https://www.facebook.com/TheKingOfRandom/videos/3916373305264694/?mibextid=9drbnH&s=yWDuG2&fs=e
2025-07-08 Full Restoration Of Old AM Transistor Radio
This is hard to believe. It’s a lot of work to do on a cheap AM radio. But it gives me a lot of ideas. I wonder how many hours it took to do this, we see it happening in nust a few minutes. https://www.facebook.com/restorationpretty/videos/591611740013679/?mibextid=9drbnH&s=yWDuG2&fs=e
2025-03-15 Specially Made Wrench Fits Odd Sized Bolts
https://www.facebook.com/reel/1817299472352574/?mibextid=9drbnH&s=yWDuG2&fs=e
2024-08-31 AM Transmitter, Low Power
This is an AM transmitter that this guy built. He says it’s rich in harmonics – it has no tuning nor low pass filtering and the stages are class C, no forward bias. It should have all the things used to minimize harmonics, like a low pass filter. Class C operation is used to maximize
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2024-08-21 Adjustable Power Supply Uses Sziklai Pair
This messy bunch of parts is a 0 to 9V adjustable power supply. The original power supply board connected the two transistors in the Darlington Configuration. The unregulated 12V input goes through a 187 ohm resistor to a 10V zener diode to give a stable reference voltage. This voltage is fed to a 2.5k linear
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2024-05-29 Solar Panel Controller To Charge Lead-Acid Battery
This is a simple charge controller that includes a dump load to dissipate excess power from the PV panel. D1 is the reference voltage that feed the 393 comparators, and its forward voltage changes with temperature. It would be better to use a low power LM317 to give a stable 1.25 volts. Instead of a
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2024-05-13 Autonomous Solar Tracking System
For each direction of travel, it consists of two solar cells connected in parallel opposing to a motor that’s geared down to turn the tracking so both solar cells are in the shade. https://www.facebook.com/reel/7341922389263306?mibextid=9drbnH&s=yWDuG2&fs=e
